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Any one of a family of enzymes, also known as hyaluronate lyases or spreading factors, produced by mammals, reptiles, insects, and bacteria, which catalyze the breakdown of hyaluronic acid. Some hyaluronidases also attack other similar polysaccharides. Since all liquefy the polysaccharide gel which fills the tissue spaces, they effectively accelerate diffusion so that injected, dissolved, or particulate matter (bacteria, viruses, toxins, or pigments) can diffuse through a larger volume of tissue. See Hyaluronic acid

The biological importance of the enzyme depends upon its source. That found in the culture filtrates of many strains of virulent bacteria permits the microorganisms to gain access to a larger volume of the host's tissue and, hence, to additional nutriment. That found in the venom of certain snakes and bees permits the toxin to produce more extensive damage to the victim. See Enzyme


Any one of a family of enzymes which catalyze the breakdown of hyaluronic acid. Also known as hyaluronate lyase; spreading factor.
References in periodicals archive ?
Without invasin on their surface, the Yersinia bacteria are invisible to the body's immune system, thus making it possible for RovA to now activate other genes in the bacteria to adapt the Yersinia metabolism with that of the host.
This difference and one in the invasin gene account for Y.
Some strains are resistant to multiple antibiotics and possess virulence factors, such as adhesins, invasins, pili, and haemolysin (Willems et al.
Of all Hae-specific genes, >22% encoded homologs of products identified elsewhere as being involved in host--pathogen interactions; prominent members were putative adhesins and invasins not previously found in strains of H.
Certain less adherant strains invaded well, suggesting they might express different invasins that mediate rapid internalization.
These include: (i) adhesions, which promote microbial adherence to host tissues; (ii) invasins, which are responsible for tissue invasion; (iii) impedins, molecules which allow microbes to overcome host mechanisms; (iv) aggressins, factors which promote damage to host cells and tissues; and (v) immunomodulatory microbial components.